Alright driver guru's, please give opinion on this driver...

I found some of these drivers for two dollars each in a 17mm round rated for up to 8.4 VDC input and 1000ma out. I've been hunting high and low for a 400ma output 17mm round driver which could run off of 8.4 VDC, modifying this looks like my ticket., what do you think?

Do you need more than one? Survival Laser sells one that is adjustable from 400mA to 1.1A, but they are $20.
Survival Laser Adjustable Current Driver

Alan

Thanks Pi, looking at it, looks good.

By the way, checking out his drivers I found the specs for one he is offering:

Specifications:
Diameter: 16.84mm +/- .05mm
Input Voltage: 1.2*Vin - 16V
Output Voltage: <1V - 9V
Output Current: 1.5A - 3A (varies slightly per board)
Ripple Current: <100mA
Input Spike Current: <100mA
Efficiency: 85-90%
Circuit Continuity: Isolated D- and D+

Survival Laser Driver

NOW THAT'S THE PROPER WAY TO LIST DRIVER SPECIFICATIONS!!! Are you other driver sellers listening? Why don't you give this information?

Alaskan said:

modifying this looks like my ticket., what do you think?

Click to expand...

Yes. Change R250 to about R625.

R250 is clearly the current shunt because of its low value. If it's 1000mA, it follows the feedback voltage is 0.25V. Use ohm's law and adjust the shunt as you please. 0.25V/0.625ohm=0.4A

Alaskan said:

Are you other driver sellers listening? Why don't you give this information?

Click to expand...

The specks for at least some of the drivers
are available in the Driver Specifications
Compendium thread.

Thanks TLS & Cyparagon. Simple fix for that driver, tks!

Re: driver specs, it's just that when I go to a sellers web page and see most if not all of this information missing, it is very frustrating to me not to see the full specs as an electronics tech by trade. When I asked one seller why he doesn't list the specs right next to picture of the driver with the buy it button, he remarked his buyers know what they want already or understand which driver they need. OK, that's reasonable, anyone who buys them knows what they are doing... but what about the people who don't buy them because they don't know anything about it without the specs? (bang head on wall) I could just about spit nails over this stuff.

Need to knows:

Input voltage range
Output voltage range
Output current range (as well as adjustment range, if an adjustment pot)
Drop out voltage
Efficiency as well as duty cycle at full output, whether heat sinking is needed for full output.
Is there an over temp cut off?
Continuous positive, negative or isolated?

survival laser went even further and privided ripple information with the above listing I quoted. I will soon be buying.